top of page
Dendrolycopodium obscurum
(L.) A.Haines
Flat-branched Tree Clubmoss
Lycopodiaceae
Dendrolycopodium obscurum is a species of lycopod in the family Lycopodiaceae. It is native to eastern North America and East Asia.
1/3
Description
Dendrolycopodium obscurum is a short, trailing plant that spreads via underground stems. The above-ground portions of the plant are short, forking many times into a fan shape. The main stem has leaves that are appressed to the stem, and are needle-like, about 3.5 to 4.5 mm long. The lateral branches, and have six ranks of needles: two ranks of needles directly above and below the branch, and four coming out horizontally. These needles are about 2.5 to 5.5 mm long, but the needles above and below the branch are shorter and more appressed, making the branches appear flat in cross section. Reproductive structures are called strobili; they are narrow, 1.2 to 6.0 cm long and are columnar, found in clusters of 1 to 6 on top of the plant (FNAEC 1993).
Similar species of Dendrolycopodium are Hickey’s club-moss (Dendrolycopodium hickeyi) and the prickly tree club-moss (Dendrolycopodium hickeyi). The two can be distinguished from Dendrolycopodium obscurum by having lateral branches that are not flat in cross section, but the latter has leaves on the main stem that are spreading, not appressed (FNAEC 1993).
Similar species of Dendrolycopodium are Hickey’s club-moss (Dendrolycopodium hickeyi) and the prickly tree club-moss (Dendrolycopodium hickeyi). The two can be distinguished from Dendrolycopodium obscurum by having lateral branches that are not flat in cross section, but the latter has leaves on the main stem that are spreading, not appressed (FNAEC 1993).
Uses
Note: Please see the disclaimer regarding any information about medical or edible uses.
Appearing like miniature Christmas trees, Dendrolycopodium obscurum and related species are often harvested for Christmas decorations, but this is discouraged as they do not recover well from such harvesting (Williamson 2021).
Distribution
Dendrolycopodium obscurum is found in rich hardwood forests and shrubby areas, at elevations up to 1600 m. It is distributed from northern Wisconsin and Ontario east to Nova Scotia, south to Ohio and northern Georgia and Alabama (FNAEC 1993); separate populations also exist in Northeast China (Heilongjiang, Jilin, Liaoning), Korea, Japan, and eastern Russia (Wu et al. 2013).
Status
References
FNAEC (Flora of North America Editorial Committee), editor. 1993. Flora of North America, north of Mexico. Volume 2: Pteridophytes and Gymnosperms. New York: Oxford University Press.
Williamson, J. 2021. Clubmoss. Home & Garden Information Center. [accessed 2021 May 11]. https://hgic.clemson.edu/factsheet/clubmoss/
Wu, Z. Y., Raven, P. H., and Hong, D. Y., eds. 2013. Flora of China. Vol. 2-3 (Lycopodiaceae through Polypodiaceae). Beijing: Science Press, and St. Louis: Missouri Botanical Garden Press.
Williamson, J. 2021. Clubmoss. Home & Garden Information Center. [accessed 2021 May 11]. https://hgic.clemson.edu/factsheet/clubmoss/
Wu, Z. Y., Raven, P. H., and Hong, D. Y., eds. 2013. Flora of China. Vol. 2-3 (Lycopodiaceae through Polypodiaceae). Beijing: Science Press, and St. Louis: Missouri Botanical Garden Press.
Description
bottom of page